Nozzle for spray guns



Nov. 4, 1941. R. R. PELLAR NOZZLE FOR SPRAY GUNS Filed March 2, 1940 u llllllllll.

lll I mi IHIIIIII In f/ezzor: Ric rd 1x2/larf farw gy Patented Ney. 4, 1941 NozzLE Forl SPRAY GUNS Ralph Richard Pellar, Chicago, Ill. Application March Z, 1940, Serial No. 321,883

3 Claims.. (C1. 299-141) v My invention relates to anozzle or' spray-head for a spray-gun or airbrush'used for spraying 'paint or other surface coating materials and like purposes.

Supplemental air streamsissuing from ports disposed on opposite sides of the rmaterial stream` so as to converge upon and iiatten the latter ployed in such devices but the yresulting spray is unevenly distributedeither split in the middle or heavy at the edges.` My invention is intended to remedy this fault. f

An object of my invention is to provide simple and eliicient means for forming a fan-like spray of material of approximately uniform depth or thickness throughout substantially its entire width at a suitable distance in advance of the material orice. This object is accomplished in my invention by providing in the conventional type of such a nozzle or spray-head an angularlydisposed, transversely extending groove or channel in the face of each port wing in such relation to the port `of such wing and of sucih conguration that the port will be at the base of such groove and approximately midway between the ends thereof and that the side walls of such groove, respectively, will be approximately tangential to opposite sides of said port and parallel. llhe side walls of such groove restrict the stream vof air issuing from the port in each of two opposite directions but it is free to spread laterally in either direction, thus causing the air stream to become substantially flattened. Two such streams of air convergingupon the material stream issuing from a central orifice cause the latter stream to spread evenly and become substantially fan-like and of approximately uniform thickness or depth throughout substantially vits entire width, thus avoiding the bulges and uneven distribution of material generally experienced with devices of the prior art.

In the drawingorifice 2.

,v and vproduce a fan-like spray are "commonly ernl 4, 4 approximately midway between the sides thereof and a suitable distancein advance of The ports 3, 3 are connected with a suitable air source through channels L5, 5 and 6, 6, channels 5, 5 being disposed' at a suitable angle, Qpreferably 45, and veach of such design and so positioned, respectively, as to project contance in front of said orifice and in a plane at thev channels 5, 5.- In the form shown in Figs. 1,

2, 3 and 4, the grooves 1, 'l are circumferentially disposed with respect to the material discharge axis 2a (this facilitates manufacture in that the nozzle may be placed in a lathe and revolved and the slots or grooves readilycut); the plane of the base 8 is perpendicular to the air discharge axis 3a and the side walls .1l2L and 9b thereof and the axes 3a, 3a of the ports 3, 3 are disposed at an angle of substantially 45 with the axis 2iL but in the same plane therewith.

The conguration of Athe various parts, including the ports 3, 3 and the channels or grooves 1, 1, may be varied to suit the requirements of par 'ticular undertakings.

The depth of the grooves 1, 1 depends upon the size of the air ports 3, 3, the width of the spray pattern desired, and the air pressure to be applied; e. g., to obtain a spray Fig. 1 is a side View of a device embodying my invention, diagrammatically shown.

Fig. 2 is an end view of such a device.

Fig. 3 is a top or plan View of the same device.

Fig. 4 is a central sectional View of the device shown in Fig.V l.

Referring to the drawing, Figs. 1 to 4, inclusive, my invention may be described as follows:

The nozzle or spray-head Il has a central material orice 2, of any suitable shape but preferably circular. In the same axial plane are air ports 3, 3 also of any suitable shape but prefpattern of 10 to 12 spread and a depth of 1 to 11A using a material orice of No. 32 drill andan'air port of No. 55 drill, the groove may have a width equal to that of the No, drill and a depth of approximately .030", the axes of the air ports being at an angle of approximately 45 with the material discharge axis. The groove will ordinarily extend the full width of the port wing.

I-Iaving thus described my invention, I claim:

1.\A nozzle for a spray-gun having a central outlet, two opposed forwardly projecting outer' horns, and two oppositely disposed, substantially circular air ports; each of said horns having an oblique inner face with a transversely extending, regressively-arcuate groove therein substan` tially in advance of said outlet; said grooves being approximately lsymmetrical and circumferenerably circular, oppositely disposed in port wingsv55 tially disposed with respect to the axis of `said,

outlet, and one of said ports being positioned about midway between the ends and substantially at the base of each of said grooves and approximately tangential to the side walls thereof; the axes of discharge from said ports lying in a plane common to the axis of discharge from said outlet and converging with said axis substantial- 1y in advance of said outlet.

2. A nozzle for a spray-gun as set forth in claim ports is ysuch as substantially to flatten air streams issuing from said ports so as to produce a material stream of substantially fiat pattern.

3. A nozzle for a spray-gun as set forth in claim 1in which the sidewalls of the respective grooves are concentric, the ends of the grooves are open, and the conguration of the ports and grooves is such that the converging streams of air will fiatten the material stream into a fan-shape of sub- 1 in which the grooves are open at their ends 10 stantially uniform cross-section.

and the configuration of the grooves and air RALPH RICHARD PELLAR. 

